Hi Katie,
Maybe you saw a bolide (see for example
http://www.youtube.com/watch?v=RrL-cWaYdno). The word bolide comes from the Greek bolis which can mean a missile or to flash. The IAU has no official definition of bolide and generally considers the term synonymous with fireball. The bolide term is generally used for fireballs reaching magnitude -14 or brighter.
Regards
Peter